Posts

Evaluation of audio test methods and measurements for end-of-line loudspeaker quality control

In order to minimize costly warranty repairs, loudspeaker OEMS impose tight specifications and a “total quality” requirement on their part suppliers. At the same time, they also require low prices. This makes it important for driver manufacturers and contract manufacturers to work with their OEM customers to define reasonable specifications and tolerances. They must understand both how the loudspeaker OEMS are testing as part of their incoming QC and also how to implement their own end-of-line measurements to ensure correlation between the two.

Authors: Steve Temme, Listen, Inc. and Viktor Dobos, Harman/Becker Automotive Systems Kft.
Presented at ISEAT 2017, Shenzhen, China

Full Paper

In-Vehicle Distortion Measurement

Authors: Zarina Bhimani, Steve F. Temme (Listen, Inc.), Patrick Dennis (Nissan Motor Co.).  Reprinted from the 2017 Loudspeaker Industry Sourcebook.

Steve Temme and Patrick Dennis discuss their research exploring test methods that will help determine audible distortion and enable manufacturers to test sound equipment after it is installed

Full Article

 

 

New Speaker Testing Brochure

lisBrochureSpeakers.inddA new 4 page brochure outlines Listen’s capabilities in loudspeaker and  microspeaker testing. SoundCheck offers simple, fast and accurate testing of any loudspeaker – no matter what the form  factor, functionality, connector or additional features. It measures a full range of driver parameters via traditional analog or digital, wireless/Bluetooth, Toslink, HDMI or USB connections, as well as microphone performance, surround sound and more.
Measurements that SoundCheck can make include:

  • Frequency response
  • Phase & polarity
  • Distortion: harmonic, IM, multitone & non-coherent
  • Rub & Buzz (inc. Perceptual Rub & Buzz)
  • Impedance
  • Directivity (including polar plots)
  • Max SPL
  • Power rating tests
  • Simulated free field measurements
  • Thiele-Small parameters
  • Time-frequency analysis

Download brochure    download_pdf_icon

Measurement of Harmonic Distortion Audibility Using A Simplified Psychoacoustic Model

A perceptual method is proposed for measuring harmonic distortion audibility. This method is similar to the CLEAR (Cepstral Loudness Enhanced Algorithm for Rub & buzz) algorithm previously proposed by the authors as a means of detecting audible Rub & Buzz which is an extreme type of distortion[1,2]. Both methods are based on the Perceptual Evaluation of Audio Quality (PEAQ) standard[3]. In the present work, in order to estimate the audibility of regular harmonic distortion, additional psychoacoustic variables are added to the CLEAR algorithm. These variables are then combined using an artificial neural network approach to derive a metric that is indicative of the overall audible harmonic distortion. Experimental results on headphones are presented to justify the accuracy of the model.

Authors: Steve Temme, Pascal Brunet and Parastoo Qarabaqi
Presented at the 131th AES Convention, San Francisco, 2012

Full Paper